Conversion of Expression in Automapper

It looks like you are trying to pass an expression that references ProductEntity to a method that expects an expression that references tblProduct, and AutoMapper is not handling the conversion correctly. You can try updating your AutoMapper mapping configuration to include a mapping from ProductEntity to tblProduct, like this:

MapperConfiguration _config = new MapperConfiguration(cfg => {
    cfg.CreateMap();
    cfg.CreateMap>, Expression>>();
});

This should allow AutoMapper to convert the expression parameter correctly when you call _Mapper.Map.

using System;
using System.Data;
using System.Data.SqlClient;
using DocumentFormat.OpenXml;
using Excel = Microsoft.Office.Interop.Excel;


namespace projectdemosql
{
    class Program
    {
        
        public static void  GetData()
        {
            SqlConnection con = new SqlConnection("Data Source=LAPTOP-C66D0I8E\\SQLEXPRESS;Initial Catalog=demoproject;Persist Security Info=True;User ID=sa;Password=navya1920");
            SqlCommand cmd = new SqlCommand("select * from college", con);
            SqlDataAdapter da=new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds,"tbdata");

            var excelApp = new Excel.Application();
            excelApp.Workbooks.Add();

            // single worksheet
            Excel._Worksheet workSheet = excelApp.ActiveSheet;

            // column headings
            for (var i = 0; i < ds.Tables["tbdata"].Columns.Count; i++)
            {
                workSheet.Cells[1, i + 1] = ds.Tables["tbdata"].Columns[i].ColumnName;
            }

            // rows
            for (var i = 0; i < ds.Tables["tbdata"].Rows.Count; i++)
            {
                // to do: format datetime values before printing
                for (var j = 0; j < ds.Tables["tbdata"].Columns.Count; j++)
                {
                    workSheet.Cells[i + 2, j + 1] = ds.Tables["tbdata"].Rows[i][j];
                }
            }

            string excelFilePath = "D:\\Excel Sheets\\sample.xlsx";
            // check file path
            if (!string.IsNullOrEmpty(excelFilePath))
            {
                try
                {
                    workSheet.SaveAs(excelFilePath);
                    excelApp.Quit();
                }
                catch (Exception ex)
                {
                    throw new Exception("ExportToExcel: Excel file could not be saved! Check filepath.\n"
                                        + ex.Message);
                }
            }

            // send an email

        }


        /// 

        /// The main entry point for the application.
        /// 
        static void Main()
        {
            GetData();
        }
    }
}

I am done this code soo  need to related code mail send to excel code to use this code please send the code before check my code